'\" et
.TH AIO_RETURN "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\"
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.\"
.SH NAME
aio_return
\(em retrieve return status of an asynchronous I/O operation
.SH SYNOPSIS
.LP
.nf
#include <aio.h>
.P
ssize_t aio_return(struct aiocb *\fIaiocbp\fP);
.fi
.SH DESCRIPTION
The
\fIaio_return\fR()
function shall return the return status associated with the
.BR aiocb
structure referenced by the
.IR aiocbp
argument. The return status for an asynchronous I/O operation is the
value that would be returned by the corresponding
\fIread\fR(),
\fIwrite\fR(),
or
\fIfsync\fR()
function call. If the error status for the operation is equal to
.BR [EINPROGRESS] ,
then the return status for the operation is undefined. The
\fIaio_return\fR()
function may be called exactly once to retrieve the return status of a
given asynchronous operation; thereafter, if the same
.BR aiocb
structure is used in a call to
\fIaio_return\fR()
or
\fIaio_error\fR(),
an error may be returned. When the
.BR aiocb
structure referred to by
.IR aiocbp
is used to submit another asynchronous operation, then
\fIaio_return\fR()
may be successfully used to retrieve the return status of that
operation.
.SH "RETURN VALUE"
If the asynchronous I/O operation has completed, then the return
status, as described for
\fIread\fR(),
\fIwrite\fR(),
and
\fIfsync\fR(),
shall be returned. If the asynchronous I/O operation has not yet
completed, the results of
\fIaio_return\fR()
are undefined.
.P
If the
\fIaio_return\fR()
function fails, it shall return \-1 and set
.IR errno
to indicate the error.
.SH ERRORS
The
\fIaio_return\fR()
function may fail if:
.TP
.BR EINVAL
The
.IR aiocbp
argument does not refer to an asynchronous operation whose return
status has not yet been retrieved.
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fIaio_cancel\fR\^(\|)",
.IR "\fIaio_error\fR\^(\|)",
.IR "\fIaio_fsync\fR\^(\|)",
.IR "\fIaio_read\fR\^(\|)",
.IR "\fIaio_write\fR\^(\|)",
.IR "\fIclose\fR\^(\|)",
.IR "\fIexec\fR\^",
.IR "\fIexit\fR\^(\|)",
.IR "\fIfork\fR\^(\|)",
.IR "\fIlio_listio\fR\^(\|)",
.IR "\fIlseek\fR\^(\|)",
.IR "\fIread\fR\^(\|)"
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "\fB<aio.h>\fP"
.\"
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
.PP
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
